A Multiagent System for Optimizing Urban Traffic

For the purposes of managing an urban traffic system, a hierarchical multiagent system that consists of several locally operating agents each representing an intersection of a traffic system is proposed. Local Traffic Agents (LTAs) are concerned with the optimal performance of their assigned intersection; however, the resulting traffic light patterns may result in the failure of the system when examined at a global level. Therefore, supervision is required and achieved with the use of a Coordinator Traffic Agent (CTA). A CTA provides a means by which the optimal local light pattern can be compared against the global concerns. The pattern can then be slightly modified to accommodate the global environment, while maintaining the local concerns of the intersection. Functionality of the proposed system is examined using two traffic scenarios: traffic accident and morning rush hour. For both scenarios, the proposed multiagent system efficiently managed the gradual congestion of the traffic. As one roadway becomes more congested, the duration of the traffic lights of neighboring intersections leading towards the congested area are reduced by the CTA. If this reduction to the incoming traffic is insufficient, and the roadway continues to reach a congested state, then the LTA attempts to divert traffic using alternative directions.